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RFID SENIOR PROJECT

Final ReportUniversity of Maine Mechanical Engineering

Department

Adam Freund, Amanda Mayette, and Matthew Sevey

5/2/2012

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ABSTRACTThe Radio Frequency Identification senior design project was created to provide power

to a tag detection system using an alternative form of energy. The system requiring power was part of a US Geological Survey study on the migration of fish through the Dover-Foxcroft, Maine area. Wind, water, and sun light were all initial options for the source of power. An array of four solar panels was the final solution, as it proved to be the most dependable and least problematic solution. Both wind and water are dependent on the fluid flow conditions and need to be tested in controlled environments. Due to the low average wind velocities in the target area, and due to the limited amount of testing that was safely available for hydropower, these options were eventually eliminated from consideration.

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TABLE OF CONTENTSABSTRACT...................................................................................................................................... ii

TABLE OF CONTENTS..................................................................................................................... iii

TABLE OF FIGURES......................................................................................................................... v

CONTRIBUTIONS........................................................................................................................... vi

Adam Freund.............................................................................................................................vi

Amanda Mayette.......................................................................................................................vi

Matthew Sevey......................................................................................................................... vi

1.0 INTRODUCTION........................................................................................................................1

2.0 DESIGN DESCRIPTION.............................................................................................................. 1

3.0 CONCEPT DESIGN PROCESS.....................................................................................................3

3.1 System Energy Usage Requirements....................................................................................3

3.2 Power Generation Options..................................................................................................5

3.3 Selection of Components.....................................................................................................7

3.3.1 Hydro-turbine............................................................................................................... 7

3.3.2 Solar Panels...................................................................................................................8

3.3.3 Regulator...................................................................................................................... 9

3.4 Permitting and Regulatory Considerations........................................................................11

4.0 DESIGN EVALUATION.............................................................................................................12

4.1 System Testing Limitations................................................................................................12

4.2 Hydro Turbine....................................................................................................................12

4.3 Solar Panels........................................................................................................................12

5.0 CONCLUSIONS........................................................................................................................13

5.1 Solar Panels........................................................................................................................13

5.2 Hydro Turbine....................................................................................................................13

6.0 RECOMMENDATIONS............................................................................................................ 14

7.0 MAINTENANCE.......................................................................................................................14

ACKNOWLEDGEMENTS................................................................................................................16

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8.0 APPENDIX A: MECHANICAL LAB III REPORT...........................................................................17

8.1 Introduction...........................................................................................................................17

8.2 Objectives.............................................................................................................................. 17

8.3 Apparatus, Equipment and Instruments................................................................................17

8.4 Theory....................................................................................................................................21

8.5 Procedure.............................................................................................................................. 21

8.6 Results................................................................................................................................... 25

8.7 Conclusions............................................................................................................................28

9.0 Appendix B: WIND TURBINE DATA SUMMARY......................................................................28

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TABLE OF FIGURESFigure 1 – Initial Design Energy flow block diagram.......................................................................2

Figure 2 - Tag detection system.....................................................................................................2

Figure 3 - Final Design electrical diagram......................................................................................3

Figure 4 - Available Wind Power in Maine.....................................................................................6

Figure 5 – Ampair UW100 Water Turbine.....................................................................................8

Figure 6 – Solar panel in use at Witter Farm..................................................................................9

Figure 7 – Ampair Dual input 24V regulator................................................................................10

Figure 8 - Morningstar Regulator.................................................................................................11

Figure 2 - Electrical Schematic.....................................................................................................20

Figure 3 - Wind Tunnel Set Up.....................................................................................................20

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CONTRIBUTIONS

Adam FreundAdam Freund was the point person for much of the technical work, especially the electrical work that was needed for the project. Adam did that majority of the work to figure out how to properly wire the wind turbine and data acquisition system for the RFID’s wind turbine testing.

Amanda MayetteAmanda Mayette did much of the organization for the group, writing all of the initial reports, designing the group's website, and making sure important deadlines were met. She represented the group at the Engineering Expo and did the poster for the Open House presentation. Amanda was also the contact and spokesperson for the group for the first half of the project.

Matthew SeveyMatthew Sevey did the majority of the group’s revisions and compilations of reports, as well as doing an initial website design. He was the main contact person between the group and Murray Callaway for the writing and editing of the group’s final report. He was responsible for working with the DEP to resolve the issue of permits. Matthew was also the spokesperson for the group for the second half of the project.

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1.0 INTRODUCTIONThe Radio Frequency Identification (RFID) project was created to find an alternative

energy solution to reliably power a fish tag detection system at a dam lacking AC power. The dam in question is located on the Piscataquis River in Dover-Foxcroft, ME, directly in the middle of town, and is owned by the town of Dover-Foxcroft. The project directly affected the University of Maine Wildlife Ecology Department. For this reason, Dr. Joe Zydlewski, from the Wildlife Ecology Department, and Dr. Michael Peterson from the Mechanical Engineering Department, teamed up to supervise the senior design group and its progress. RFID systems are used to detect and classify fish for long-term studies of populations. This project’s outcome helped the United States Geological Survey close one of the gaps in its ability to track the fish. Studies are being performed at dams across Maine, and the lack of availability of electricity at some sites impedes the progress of biologists.

In order to be considered viable, Dr. Joe Zydlewski and his team had to agree with the completed design and be ready to install the system on the Dover-Foxcroft Dam with or without the RFID group depending on timing. The design had to be able to charge the batteries while the batteries were powering the tag reader and be able to sustain periods of low power production due to the weather and the environment.

2.0 DESIGN DESCRIPTIONThe main objective of the RFID project was to build a reliable power generation system

to run a tag detection system similar to others that were already in use at several dams across Maine. In the tag detection systems, one to six antennas read tags implanted in fish as the fish pass through the fish ladder. The information read off the tags is then sent back to the system that often is located at the top of the fish ladder. Typically, the tag detection systems were plugged into an AC outlet to get the electricity needed to power the system.

In the initial energy system designed by the RFID group, electricity to power the system flowed from two chosen sources, a solar panel and a hydro turbine, into a dual input regulator. This regulator took the two energy inputs and combined them into a single energy output that charged a battery bank which powered the tag detection system. Figure 1 shows the energy flow in a block diagram for the initial design.

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Figure 1 – Initial Design Energy flow block diagram

Figure 2 shows the tag detection system with its battery bank, charger, timer, and tag reader.

Figure 2 - Tag detection system

When it came time to test the system, the RFID group and Dr. Zydlewski decided to go with a system design that used four solar panels instead of the single solar panel and hydro turbine. This design required a new regulator that could handle the higher power output. The regulator also served as a single connection point for the solar panels, the battery bank, and the tag reading system. The final design electrical diagram is shown in Figure 3.

Tag ReaderTimer

Charger Battery Bank

Antenna Connections

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Figure 3 - Final Design electrical diagram

3.0 CONCEPT DESIGN PROCESS

3.1 System Energy Usage RequirementsThe RFID project description asked for an alternative energy solution to be developed

for use at a dam in Maine without AC power. In order to choose the power source(s) best suited to power the RFID system, the power requirements of the system had to first be determined. This was accomplished by visiting a running RFID system at the dam in Milford, Maine, as well as setting up a complete RFID system at the Deer Pens on the University of Maine campus. On both systems, various voltage and current readings were taken. Measurements were taken for different antenna configurations, sampling frequencies, and tag passing frequencies. Both typical and maximum power requirements for the system were determined using these measurements.

At the Milford Dam, the tag reading system was set up with three antennas and at a typical gain setting. The group measured the current drawn from the battery bank when the system was idle, so no tags were passing through the antennas. In this idle state, the system drew in 0.75A. Due to electronic noise in the system, the current fluctuated slightly and a maximum value for the current was measured to be 0.81A. The group also took the same measurements, but with one of the antennas unplugged to see the affect on the current. With one antenna unplugged, the system drew 0.66A.

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Table 1 shows the values of current drawn from the battery bank that were measured at the Deer Pens system:

Table 1 – Electric current data from Deer Pens system

Test Description Current Drawn (Amps)

1 System idle, one antenna, typical gain setting 0.52

2 Constant tag reading, one antenna, typical gain setting 0.53

3 System idle, one antenna, maximum gain setting 0.70

4 Constant tag reading, one antenna, maximum gain setting 0.71

5 System idle, no antenna, maximum gain setting 0.40

It was observed that the number of antennas hooked up to the system did not significantly affect the current draw since the tag reader switches through the antennas at a set sample rate.

In order to be conservative with a power requirement estimate, a design current requirement of 1.0A was chosen. This was to account for factors such as

The variations in the current as it was being measured

Deviations in how the Dover-Foxcroft and other future systems are set up and run

Temperature effects

Battery voltage degradation

The need to power additional pieces of equipment such as modems

The fact that the Multiplex Transceiver user manual indicated that the unit can draw a peak current of up to 3.0A, which was never reached with the systems current configuration.

The system required a power input large enough to charge two 12V batteries in series; this resulted in a need for 24V DC. The system had a battery bank that consisted of two of these 24V series connected in parallel. Since the two-24V series were connected in parallel, a timer

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was used to change which set of batteries was powering the system every four hours. Electricity generation had to be constant, so the alternative energy system had to ensure that one set of batteries was powering the RFID system and one set of batteries was charging at all times.

Since it was critical that the tag reader take uninterrupted measurements, the group decided that slightly overdesigning the system was the best idea in order to ensure the stability of the system, since a regulator would prevent the batteries from overcharging. With the chosen design current of 1.0A and the required 24V from the tag reader, the power requirement of the system was 24W. Equation 1 shows how power is determined from a known current and voltage.

Power = Current * Voltage (1)

This value did not account for inefficiencies in charging or storing energy in the batteries, so the actual power produced by the renewable energy system needed to be higher.

3.2 Power Generation OptionsThe three main power generation options that were considered for this project were

solar, wind, and water power, using a solar panel, wind turbine, and water turbine respectively. The three members of the group discussed many possibilities before it was decided that the best approach was to first examine the dam to determine if there were any location limitations. After the trip to Dover-Foxcroft, it was decided that the best option for this project was to use a hydro turbine to power the tag system.

Wind initially appeared to be a viable option due to the openness of the area and the strong continuous wind that was present during the group’s visit. In the end, a number of factors led to the decision to eliminate wind and to focus solely on a combination of water and solar power, even though the RFID group did have access to a free wind turbine. The RFID group tested the wind turbine so that Dr. Zydlewski and his team would have the necessary information in case they were to use the wind turbine in the future. Appendix A and B contain the lab report that the group wrote and the data collected from the wind turbine testing. Wind power proved to be the least reliable power source of the three options, especially for the area of intended use. The Dover-Foxcroft area, as well as most of inland Maine, had very low average wind speeds. Figure 4 shows the available wind power in Maine.

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Figure 4 - Available Wind Power in Maine

Through research, it was found that the average wind speed in the area near the dam was typically below 5 m/s, which was not high enough to produce appreciable power. Another consideration in mounting a wind turbine at this particular site was that the dam was located in the center of town and was easily visible. A wind turbine mounted in this location could be seen as an “eyesore” to some.

The most constant of the three power sources on a daily basis was waterpower. Since the river flows at a relatively constant speed, it was a better choice for a reliable and predictable energy source. Since the RFID tag reader was located on a dam, the pressure head created by the dam could be utilized to obtain greater water speeds.

Solar power was the most common power source for this type of project for a number of reasons. Reasonable levels of solar radiation were found essentially everywhere, except for cloudy days; the patterns, durations, and intensities of sunlight were easily and accurately predictable. Solar panels have no moving parts, require minimal maintenance, are easy to install and have a long working life.

Dover Foxcroft, ME

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Initially, a combination of a water turbine with a supplemental solar panel was chosen. The two sources complement each other. In the summer, when the water turbine would have the lowest output due to lower water levels and flows, the solar panel would be at its peak output. Since the solar panel would only be outputting power during daylight hours, the water turbine, which operates 24 hours a day, would help buffer the nighttime hours and reduce the reliance on the battery bank’s charge to make it through the night.

Hydropower, although it seems an obvious option, had not been at the top of the solutions list until after the visit to the dam. It was perceived that a small hydro turbine could be acquired to attach at the base of fish ladder where it would receive a constant flow for its power source. The turbine itself would be mounted with a cage enclosing the turbine blades to protect it from debris and to help protect the fish from the blades. Underwater turbines can be hidden from sight, receive a constant energy source from which to generate electricity, and are commodities available to be purchased online. Another upside to the choice of a hydro turbine was the financial support and interest from the Wildlife Ecology department.

Even with the all the positives of the hydro turbine, the final design consisted only of solar panels that were already owned by the Wildlife Ecology department.

3.3 Selection of Components

3.3.1 Hydro-turbine

In order to find an appropriate hydro turbine, the RFID group researched a variety of hydro turbine designs and manufacturers. Some guiding criteria that helped the group narrow down their options were the power required by the system and cost of the turbine. The RFID group found an Ampair UW100 Water Turbine that met the power requirements and was cost effective. Another factor that the group needed to consider before a turbine was purchased was at what water speed the turbine was functional. To determine what the water speeds would be at the dam, the group was assisted by Edward Hughes, a graduate student in the Wildlife Ecology Department. Mr. Hughes was able to direct the group to data that the USGS had compiled from a flow meter on the Piscataquis River upstream of the dam. The Ampair turbine that the group was interested in was recommended for use in water speeds of 1m/s or higher in order to generate acceptable power. When the RFID group looked over the USGS data for the river, they decided that on average the river would generate appropriate water speeds for the turbine to work. After all the requirements for the turbine were met, the RFID group decided to order the Ampair UW100 Water Turbine. This decision was approved by both Dr. Peterson and Dr. Zydlewski. Figure 5 shows the Ampair UW100 Water Turbine.

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Figure 5 – Ampair UW100 Water Turbine

The hydro turbine was eventually eliminated as an option. Dr. Zydlewski wanted to test the hydro turbine before it was installed on the dam in order to make sure it operated the way it was expected to. Another reason the hydro turbine was not used in the final design was because of the difficulty of installation on the dam. Since the Piscataquis River would have very high flows due to snow melt and spring rains, the turbine would not be able to be installed until late summer when the flow would be lower. The tag system was to be installed in May so the absence of the hydro turbine forced the group to consider a different design and eliminate the hydro turbine.

3.3.2 Solar Panels

Stream flow volumes can change drastically and hydro-turbines can fail, so a back-up power source was proposed for safety precautions. Due to the tag reader’s need for consistent power input, the group and its advisors discussed the addition of a solar panel to the hydro turbine. Fortunately, the Wildlife Ecology department already owned four panels that were available to the group for use at the dam. Solar had been proven in many applications, and therefore had great potential at this location. Information was readily available and limited extra expense was required in order to pursue this route.

To determine if the use of a solar panel as a backup for the hydro turbine was a viable option for that location, solar radiation data was gathered for the area and processed using the PC Insol program introduced in MEE 433, the Solar Thermal Engineering course. The information collected on October 13, 2011 proved that a solar panel would be able to provide sufficient back up power for the hydro turbine. The solar panels available for the group had

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directions that instructed users that the tilt of the panel from the horizontal is the latitude of its location plus 15 degrees. This meant for Dover-Foxcroft, ME, the panel should be tilted at 60 degrees. The panels provided to the group for use are Solarex MSX-60 and in order to confirm the output rating on the panel specifications, the group tested one of the solar panels at UMaine’s Witter Farm. Based on the open circuit voltage of 21.5V and the short circuit current of 1.05A that the panel was able to produce in February, it was determined that one panel would be sufficient back up power. Figure 6 shows the solar panel in use at Witter Farm.

Figure 6 – Solar panel in use at Witter Farm

With the elimination of the hydro turbine, the need for more solar panels was evident. Since there was a need for 24V and each solar panel could be configured for 12V, at least two solar panels were needed. Dr. Zydlewski and the group decided to use all four solar panels to get the most out of days with low solar radiation.

3.3.3 Regulator

In order for the system to receive the power generated by both alternative energy sources of the initial design, a dual input regulator was needed to streamline the power into one input for the system. An Ampair 24V Dual Input Single Battery Bank Regulator was ordered based on its compatibility with the hydro turbine and the system’s power requirements. The

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regulator was rated for 100W for each input which was enough to handle the hydro turbine’s 100W and the solar panel’s 60W. The company that manufactures the hydro turbine recommended this model of regulator, and after researching other brands, the team found it to be the most cost effective option as well. Figure 7 shows the Ampair Dual Input 24V regulator.

Figure 7 – Ampair Dual input 24V regulator

For the final design with the four-60W solar panels, a new regulator was needed in order to handle the 240W. In order to handle the maximum power output of the four-panel solar array, the group purchased a Morningstar ProStar PS-15 solar controller. It was a mid-range solar controller specifically designed for use with solar panels and battery banks. It could be used in both 12V and 24V systems. It was rated for 15A, which means that when used in its 24V mode, the regulator was capable of accepting up to 360W, which was well over the minimum requirement of 240W. This also increased the controller’s versatility for other future configurations and uses. The controller was a PWM (pulse width modulated) controller, which allowed it to more efficiently use the available solar power to charge the battery bank than typical shunt or on/off controllers. It was also chosen for its additional features, ease of setup, and reliability (it had an estimated working lifespan of 15 years). Additional features included the ability to switch between three different battery types to improve efficiency and battery lifespan, temperature compensated charging, status LED’s, and remote battery voltage sense terminals to compensate for line losses. The controller was different from the previous regulator in that the tag reader could be wired directly into the controller. This helped simplify the system, made setup easier, and provided a more reliable and constant power source for the tag reader and modem. Figure 8 shows the Morningstar regulator.

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Figure 8 - Morningstar Regulator

3.4 Permitting and Regulatory ConsiderationsThe legal regulations on the hydro turbine were looked into to determine the range of

permit requirements, which had the potential to go as high as the Federal Energy Regulatory Commission (FERC). Dr. Zydlewski and the group placed a call to Noah Fisheries to determine the extent of regulations for the installation of a hydro turbine at the dam. Since none of the produced power was being dispensed beyond the site, there were no federal regulations on it. Next, it was necessary to discover if any state regulations prevented its installation and use.

Norm Dube, from the Department of Marine Resources, was contacted by email in regards to this inquiry on October 20, 2011. Mr. Dube directed the group to Jim Beyer who works at the Maine Department of Environmental Protections for the Division of Land Resources Regulation. The same information was requested from him, and the following statement was Mr. Beyer’s response:

“In Maine there is a law titled the Maine Waterway Development and Conservation Act (38 M.R.S.A. §§ 630 to 640). It is a one-stop law for hydropower development. The addition of a turbine at an existing dam would require a permit under this law. I have attached some information concerning this law. You can also go to www.maine.gov and search for this law if you want to read it. You should also query the Maine Rivers Policy, (12 M.R.S.A. §§ 401 to 407).”

After looking into the relevant law and policies, the group again contacted Beyer on February 7, 2012 in order to confirm that no permits were required. It at first appeared as if a Maine Waterway Development and Conservation Act (MWDCA) permit would be required due to the implementation of a “hydropower project.” However, Jim informed the group that since the project was a closed circuit in which no generated electricity would be sent to the grid, there were no laws violated by the project installation. Instead, it would be considered

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experimental testing as oppose to a new hydropower project. This is partly because the hydro-turbine system would not be generating power all year, but only during the six or seven spring and summer months during which the RFID system was running.

4.0 DESIGN EVALUATION

4.1 System Testing LimitationsDue to access issues and safety concerns, the RFID group was unable to install the tag

reading system along with the alternative energy system on the Dover-Foxcroft Dam in order to test the design. Since there was a good chance that Dr. Zydlewski and his team would be installing the tag system on the dam without the help of the RFID group, Dr. Zydlewski wanted to test the design somewhere on campus where its effectiveness could be monitored.

4.2 Hydro Turbine In order to test the hydro turbine, the RFID group had to find somewhere, either in a

river or in the tow tank on campus, that they could safety test and collect data from the hydro turbine. The tow tank was quickly eliminated due to its inability to produce speeds fast enough. The hydro turbine had a minimum start up speed of 1m/s and the tow tank’s speed limit was 0.9m/s. The group also went around the Orono and Old Town area with a flow meter to see if they could find a location that they could safely access to test the turbine. It quickly became evident that the only places where the rivers were flowing fast enough were at the dams. While this was good news for when the hydro turbine would hopefully be installed on the Dover-Foxcroft dam, it was not very helpful to the RFID group’s desire to test the turbine because there was no safe way for the group to test the turbine near or on the dams.

4.3 Solar PanelsThe RFID group, with the help of Doug Sigourney and Andy O’Malley from the Wildlife

Ecology department, set up the four solar panels out at the Deer Pens for testing. A tag reader was also set up so that the group could see how the system would work if only the solar panels were powering the system. The four solar panels were wired such that were two pairs in parallel and each pair was two panels in series. This set up of the solar panels delivered roughly 40V. The solar panels were connected to the system through the regulator, which would bring the 40V down to the voltage required to charge the batteries.

At the other sites where tag readers were already installed, the system had a timer that switched which battery bank was being charged and which was powering the system. The main reason for the timer was to reduce the electrical noise from the grid going to the system. Since the solar panels were off the grid, the group decided to bypass the timer and measure how

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much noise the solar panels generated. Eliminating the timer eliminated the problem of figuring out the best time intervals for the timer to switch the batteries, which would be an issue since the solar panels only charged the batteries during the daytime.

It was during the testing of the solar panels that the RFID group discovered that the Ampair regulator they had bought for use with the hydro turbine and a single solar panel was not compatible with the power output from the four solar panels. Once the Morningstar regulator was hooked up to the solar panels, the RFID group was able to connect the system and test their design.

The group then connected the batteries, solar panels, and regulator up to the tag system and left it to run for a few days in order to see how the solar panels would handle charging the batteries while they were powering the system. When the RFID group checked on the system, they found that the batteries still had a charge and the system was still running. In addition, with the help of the Wildlife Ecology department, the noise coming from the solar panels was measured and it was determined that although there was a large amount of noise coming from the solar panels and regulator, but the noise was not interfering with the tag detection.

5.0 CONCLUSIONS

5.1 Solar PanelsAfter the successful testing of the solar panels, the RFID group and Dr. Zydlewski’s team

decided that when the tag system is installed on the Dover-Foxcroft Dam, they would use all four solar panels to power the system. The testing showed that the solar panels were able to balance out the power draw even during heavy rainfall and on overcast days, which meant that the system would be able to run continuously for extended periods of limited sunlight. During testing, the two 18-amp hour batteries used to power the system had enough capacity to maintain power to the system overnight, even when the previous day had low levels of sunlight.

5.2 Hydro TurbineDue to the RFID group being unable to safely test the hydro turbine, and the solar

panels being able to successfully power the system and keep the batteries charged, Dr. Zydlewski and the RFID group decided to not use the hydro turbine. Something that also factored into this decision was that the hydro turbine would not be able to be installed until later in the summer months when the water level was at its lowest. Dr. Zydlewski decided to return the hydro turbine as a result of it not being used in the final design.

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6.0 RECOMMENDATIONSThe first main recommendation from the group is the need to monitor the system more

carefully than tag reading systems installed on other dams. The reason behind this recommendation is the increased wear on the batteries due to them being charged by the solar panels during the day, and then significantly depleted at night. The RFID group recommends that the persons responsible for the system keep track of the effectiveness of the solar panels in various weather conditions, so that when extended periods of bad weather are forecasted, they will be able to determine if the system will continue to operate or if it will automatically shut down. The regulator that was used has a low voltage cut off so when the 24V battery bank falls below 22.8V, the regulator cuts off the load, which in this case is the tag reader. This helps prolong the battery life by not allowing the batteries to become completely drained. It also is recommended that when installing a similar system, the persons involve look into using a regulator like this one that has safety features to protect the system.

While the two 12V 18-amp hour batteries used during testing succeeded in maintaining power to the system over a several day period of rainy and overcast weather, the team recommended using a larger capacity battery bank in order to provide more security against losing system power over extended periods of low light. This could be accomplished by using more and/or larger batteries. The larger the battery bank, the lower the chance of the batteries becoming depleted. A higher capacity battery bank also would lead to longer lifespan of the batteries since the individual batteries would not become as depleted during times of low sunlight and overnight. A 24V battery bank with a rating of at least 60 amp hours is recommended to provide substantial security against losing system power. Anything larger than this would still provide some but very limited additional benefits due to diminishing returns.

7.0 MAINTENANCETable 2 lists some maintenance that is needed for the system. The system as a whole is

quite durable so little maintenance is needed. Since Dr. Zydlewski’s team has many of these systems already in use, they are knowledgeable in what is needed to keep the tag reader system up and running. The only difference between the Dover-Foxcroft system and the old systems is the regulator and the solar panels. Solar panels have no moving parts and therefore require little to no maintenance to keep them running. The regulator is also durable and will be installed along with the tag reader out of the way and safe from the elements.

Table 2 - Maintenance for system

Part Maintenance Description Frequency Priority

System Removal and Removal in November Low

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Reinstallation Reinstallation in May

System General cleaning and repair after removal

Once a year when removed Low

System Storage when not in use From November to April Low

Solar PanelsEnsure that solar panels access to sunlight is not

obstructed.

When needed (system loses power) Low

Regulator Ensure that regulator is oriented vertically Installation in May High

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ACKNOWLEDGEMENTSThe RFID group would like to thank the following individuals for their contributions to

this senior capstone project:

“Mick” Peterson, the senior design professor, served as the group’s main advisor throughout the entire process. He helped with all of the ordering, overcoming project obstacles, and keeping the group on task.

Joseph Zydlewski served as a second advisor for the project. He helped the group obtain the hydro turbine by taking on half of the cost as well as securing four solar panels and a wind turbine at no cost. He kept up to date with the group throughout the entire year and occasionally took it upon himself to help communicate with officials such as Noah Fisheries on the group’s behalf.

Edward Hughes, a graduate assistant in the Wildlife Ecology Department, who worked side-by-side with the group for the first half of the project to field questions on the system and the objectives of the project. Ed worked with the town of Dover-Foxcroft to get the group permissions to the property for any further testing and installation.

Andy O’Malley, a graduate student in the Wildlife Ecology Department, assisted with the two set ups of the test systems at the Deer Pens on campus.

Doug Sigourney, a graduate student in the Wildlife Ecology Department, became involved with the project in March 2012. Doug helped with the testing of the solar panels and was involved in seeing the project to the end of the semester.

Mechanical Engineering Department and Wildlife Ecology Department provided financial funding for the RFID project.

Murray Callaway who instructed the group on proper writing and formatting of final report as well as taking time to meet every other week to discuss progress on the writing process.

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8.0 APPENDIX A: MECHANICAL LAB III REPORT

8.1 INTRODUCTIONThe purpose of the experimental work is to determine the power output of a wind

turbine of unknown origin. The turbine for the experiment was provided to the group by Dr. Joe Zydlewski, who is the Assistant Unit Leader-Fisheries at the Maine Cooperative Fish and Wildlife Research Unit and Assistant Professor of Wildlife Ecology at the University of Maine. It appears to be in good condition and would be expected to still reach its full output potential, however paperwork was lost in the transition and there is no record of performance specifications.

The experiment consists of mounting the wind turbine in the wind tunnel located in Crosby Hall Room 201. The turbine is tested at a variety of wind speeds and the power output (determined from the voltage and current) is measured using LabVIEW. For each wind speed, the turbine will be aligned such that the highest output possible is achieved. Using this data, a power curve for the turbine will be produced and analyzed. The minimum power output that the turbine must produce in order to be useable by Dr. Zydlewski is 24 W at a minimum of 24 VDC.

8.2 OBJECTIVES

1) Use LabVIEW to measure the voltage and current produced by the wind turbine at various wind speeds. The current and voltage will be measured in DC amps and volts respectively.

2) Determine the power output from the information gathered. Power is voltage times current or resistance times current squared and will be given in watts.

3) Plot the power curve from the calculated information to be used as a tool for predicting output at untested wind speeds.

4) Determine if the turbine will be a sufficient source to charge a 24 V battery bank that needs to provide 24 W of constant power.

8.3 APPARATUS, EQUIPMENT AND INSTRUMENTSTable 1 - Apparatus, Equipment and Instruments

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Name Model # Serial #Info

(range, dimensions)

Mastech Multimeter MAS830L

Elenco Precision Power Supply

XP580 2N3055M0315

Dataq Instruments Isolated Volt Input Module

DI-5831-09 58010-27Input: -40V to 40V

Output: -5V to 5V

DataForth Analog I/O Backpanel

SCMPB05 57074-11Input: 5V DC, max 2800mA

National Instruments 8-Input Multifunction I/O

USB-6009 14B003C 200mA Max

Low Current Sensor Board ACS712

Input: 5V

Max Current: 5 Amps DC/AC

Gain: 4.27-47

Adjustable Resistor Range: 0-500

3 Phase Ac to DC converter

Antec Computer with LabVIEW

Alnor CompuFlow CF8585 55060180

Wind Turbine Blade Diameter: 48in

Wind Tunnel 8ftx8ftx20ft

Joy Manufacturing Axivane Fan

38-26-1770AP SF-539212300 cfm, Rated for 40hp, Max 50hp

Figure 1 shows the wiring set up for the experiment.

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Figure 1 - Wiring for data acquisition

Figure 2 shows the electrical schematic of test setup.

Figure 29 - Electrical Schematic

Data Acquisition Modules

Adjustable Resistor

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Figure 3 shows the wind tunnel and the locations of the fan, anemometer, and wind turbine.

Figure 310 - Wind Tunnel Set Up

8.4 THEORYEquation 1 shows how the power is determined from the measured voltage and current.

P= V*I=I2R (1)

The voltage and current are measured, and recorded, using LabVIEW. The total resistance applied to the turbine is measured using a hand held multimeter. A multimeter is also used to measure the voltage and current to verify the LabVIEW data. The power is determined using Equation 1.

8.5 PROCEDUREThe first step is to adjust the fan speed by setting the fan blade angles to the desired

setting. Proper lockout procedure is required on the power box in the room, to prevent possible injuries. The fan has seven blade positions, zero through six, but warning labels instruct users to only use settings four through six. Setting six produces the lowest wind speed, with the wind speed increasing as the setting number decreases. Figure 4 shows the fan blade settings.

Anemometer

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Figure 4 - Fan Blade Settings

In order to adjust the blades, the protective grating on the back of the fan first must be removed. To remove the grating, an 11mm wrench can be used to remove the bolts that hold it on. After the grating is removed, the center cover can be removed using a 13mm wrench to remove the six bolts holding the cover on. Figures 5 through 7 show the protective grating, center cover, and the exposed blade bolts.

Figure 5, 6, 7 - Protective Grating, Center Cover, Blade Bolts

To adjust the blades, a 1 ¼-inch socket is needed along with a torque wrench capable of 220 ft-lbs. Each blade must be loosened, moved to the position required, and then tightened to 220 ft-lbs. Once the blades have all been adjusted, the center cover and the protective grating can be reattached and the fan can be unlocked. Figure 8 shows the power box and lockout location.

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Protective Grating Center Cover

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Figure 8 - Power box and lockout location

Before starting testing, it is necessary to ensure that all doors to the room are locked and that the main door is bolted so that entry is impossible. Ear protection is required due to the excessive noise made by the fan. Safety glasses should be worn because of possible flying debris. Figure 9 shows the door securely latched.

Figure 9 - Door securely latched

Inside the tunnel is an anemometer for measuring the wind speed. It is extended towards to center of the tunnel as far as possible and the cap on the end is removed. There is a safety brake switch, which is switched to the brake position and then released after the LabVIEW system is up and running. The brake switch works by shorts the three-phase voltage from the turbine. This prevents the turbine from spinning when switched to the brake position. The wiring for testing and data acquisition was primarily made by reassembling the setup created by a previous group that designed and built the wind tunnel. The DataForth board is connected to the computer by via the National Instruments USB Module so that LabVIEW can be opened on the desktop to record the voltage and current. RPM can also be measured if

Lockout

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desired, provided the proper equipment is available. Figures 10 through 13 show the anemometer, brake switch, wiring board, and computer stand.

Figure 10 and 11 - Anemometer and brake switch

Figure 12 and 13 - Wiring Board and Computer Stand

The fan is turned on by holding the lever in the “start” position until the fan has reached its maximum speed (after approximately 45 seconds), and then quickly pushing the lever into the “run” position. Once the fan is running, switch the safety switch off its brake setting. Wait for the wind turbine blades to reach a steady state speed and for the LabVIEW data to level off (approximately 30 seconds). Choose a file name and directory to save the data and then click the RUN button on the screen. Each test will run for 60 seconds and will stop when the test is complete. Switch the safety brake back on. During the minute run, hand voltage and current measurements are taken to verify the LabVIEW data. The voltage reading is taken across the resistor and the current reading is taken from the current sensor (in the form of a voltage signal that must be converted) placed in series with the resistor. Alternatively, if two multimeters are available, one multimeter can be left in series with the resistor to measure current. Figures 14 and 15 show the voltage and current hand measurement procedures, respectively.

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Figure 14 and 15 - Voltage and Current Hand Measurements

This is repeated for 10 different settings of resistance, starting with the highest at 500 and going down to 50 by 50 increments. It is important not to drop below 50 so that the resistor does not burn out. This process will be repeated for each setting of blade position. Figures 16 and 17 show how the resistance is adjusted.

Figure 16 and 17 – Adjustable Resistance

8.6 RESULTSThe output of the testing, as collected in LabVIEW, is displayed below in Figures 18 and

19. These two figures show the voltage output vs. wind speed and power output vs. wind speed for the turbine respectively.

From Figure 18, a clear correlation between the wind speed and the voltage exists. As the wind increases in speed, the voltage increases as well. Since the voltage is directly proportional to the power, it also suggests that the greater the wind speed, the higher the power output will be. This is demonstrated in Figure 19 below. It is noted that the lower the resistive load applied to the turbine, the higher the power output. This is due to the current increasing proportionally as resistance decreases (Ohm’s Law). Since current has more effect on

50 increments 500

50

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power than resistance (P = I2R), lowering the resistance increased the power dissipated by the resistor. Appendix 1 is the summarized table of data recorded while testing the wind turbine.

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Figure 18 - Turbine Output Voltage vs. Wind Speed for Various Load

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Figure 19 - Turbine Power Output vs. Wind Speed for Various Loads

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8.7 CONCLUSIONSAfter completing the testing of the wind turbine, it was determined that the wind

turbine is not a suitable power source to charge the battery bank. While it was found to be functional and capable of generating the voltage needed to charge the 24 V battery bank, the power output is not great enough to keep up with the required power once real world conditions are considered. While the maximum power generated by the turbine slightly exceeds the required power, this is for wind speeds much higher than are anticipated to be continuously blowing. It is important to note that these results were achieved under a constant wind speed that is much higher than the average wind speed of the potential installation area.

For a resistive load of 50, which is very similar to that of the system to be powered, the maximum power obtained was 32.7 W. Since the maximum power output is close to the required power output (24 W), wind that is slower or intermittent will result in a power output significantly lower than required. For example, if the potential installation site has an average wind speed of about 2 m/s, using the best fit power equation for a 50 load found in Figure 19 (P = 17.387(s)^0.2161) to provide a very rough estimate of the expected average power gives an output of about 20 W. However, based on very similar wind turbines that were found online, the expected startup wind speed, that is, the minimum wind speed required for the turbine to generate any power, is about 3.2 m/s. Factoring in the inconsistency of wind, regardless of the wind turbine’s capability, it will be unable to generate the power that the battery bank requires.

9.0 APPENDIX B: WIND TURBINE DATA SUMMARYTable 3 - Summary of Wind Turbine Test Data

Summary of Wind Turbine Test Data

Test #

Resistance (Ω)

Avg Calibrated

Voltage (V)

Avg Calibrated

Current (A)

Power = VI (watts)

P = I^2*R (watts)

P = V^2/R (watts)

Average Wind Speed (m/s)

1 506 37.422452 0.062901 2.353895 2.001983 2.767668 8.41375

2 454 37.297245 0.069328 2.585754 2.182111 3.064063 8.41375

3 402 36.919976 0.074234 2.740724 2.215306 3.390758 8.41375

4 347 37.019175 0.086908 3.217260 2.620886 3.949335 8.41375

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5 299 36.691334 0.106697 3.914861 3.403901 4.502522 8.41375

6 250 36.123319 0.126361 4.564571 3.991763 5.219577 8.41375

7 203 37.304813 0.164223 6.126299 5.474730 6.855414 8.41375

8 155 37.046642 0.220025 8.151191 7.503711 8.854540 8.41375

9 102 38.453654 0.355096 13.654752 12.861528 14.496897 8.41375

10 54.1 40.483224 0.704027 28.501290 26.814895 30.293742 8.41375

11 50.5 43.387111 0.804633 34.910709 32.695445 37.276067 13.0366

12 97.9 43.892088 0.429686 18.859823 18.075297 19.678400 13.0366

13 155.2 41.670792 0.254637 10.610918 10.063155 11.188498 13.0366

14 199.3 41.103691 0.253365 10.414219 12.793785 8.477237 13.0366

15 252 45.548027 0.165456 7.536205 6.898693 8.232630 13.0366

16 301 42.218755 0.125656 5.305048 4.752632 5.921672 13.0366

17 347 42.766534 0.094827 4.055422 3.120280 5.270825 13.0366

18 399 44.583106 0.098129 4.374877 3.842059 4.981587 13.0366

19 451 47.909994 0.107260 5.138819 5.188609 5.089507 13.0366

20 505 44.660656 0.073226 3.270328 2.707845 3.949652 13.0366

21 55.4 46.183210 0.739952 34.173379 30.333141 38.499800 16.5354

22 97.8 46.622960 0.442743 20.642006 19.170921 22.225976 16.5354

23 155 47.279020 0.284272 13.440122 12.525677 14.421327 16.5354

24 198.9 47.852656 0.220826 10.567104 9.699171 11.512703 16.5354

25 250 48.506536 0.176510 8.561893 7.788953 9.411536 16.5354

26 301 49.359507 0.145338 7.173830 6.358095 8.094222 16.5354

27 355 50.553823 0.120534 6.093451 5.157592 7.199124 16.5354

28 398 51.015885 0.104471 5.329702 4.343882 6.539248 16.5354

29 454 52.420880 0.093089 4.879823 3.934190 6.052750 16.5354

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30 498 52.482170 0.084746 4.447656 3.576582 5.530880 16.5354

31 550 53.803418 0.075505 4.062425 3.135549 5.263287 16.5354

32 597 54.176289 0.071413 3.868883 3.044578 4.916366 16.5354

33 646 54.437251 0.063043 3.431880 2.567465 4.587329 16.5354

34 702 54.853771 0.055809 3.061323 2.186465 4.286234 16.5354

35 751 55.130655 0.050920 2.807264 1.947242 4.047123 16.5354

36 797 55.475797 0.048036 2.664808 1.839005 3.861435 16.5354

37 27.7 50.759996 1.002939 50.909156 27.863034 93.017227 16.5354

Notes:

For each test, the wind turbine was given time to reach steady-state conditions After steady state was achieved, current voltage data was recorded for one minute

using LabVIEW These values were average and are displayed in the table above Tests were performed with various resistive loads on the wind turbine The fan blades were configured in three orientations to produce the wind speeds seen

above Due to the considerable fluctuations of wind speed produced by the wind tunnel, the

high, low, and median range of values were collected and averaged to produce the values in the table above